Brush rigging



y 1964 v R. A. MARTIN 3,141,985

BRUSH RIGGING Filed May 4, 1961 v 2 Sheets-Sheet 1 INVENTOR. 3 RONALD ANARTIN L 9 BY HIS ATTORNEY July 21, 1964 R. A. MARTIN 3,141,985

BRUSH RIGGING Filed May 4, 1961 2 Sheets-Sheet 2 l0- h INVENTOR.

,0 I RONALD A. MARTIN 2" I 0 Z By a: R a W ms ATTORNEY United States Patent 3,141,985 BRUSH RIGGING Ronald A. Martin, Anderson, Ind, assignor to General Motors Corporation, Detroit, Micln, a corporation of Delaware Filed May 4, 1961, Ser. No. 107,812 3 Claims. (Cl. 310-239) This invention relates to brush rigging for dynamoelectric machines such as electric starting motors that are used in cranking an internal combustion engine.

One of the objects of this invention is to provide brush rigging for a dynamoelectric machine wherein a unitary piece of spring metal material serves both as a support for the brushes and also serves to urge the brushes into engagement with the commutator of the dynamoelectric machine.

Still another object of this invention is to provide a brush rigging wherein a length of spring steel material carries brush holders that are formed of insulating material and wherein brushes are carried by the brush holders.

A further object of this invention is to provide a brush rigging wherein one or more brush holders formed of insulating material have openings that receive the ends of a spring steel member which is formed with tangs that bite into the brush holder when the ends of the spring steel member are inserted into the openings of the brush holder.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention are clearly shown.

In the drawings:

FIGURE 1 is a side elevation of a starting motor that has a brush rigging made in accordance with this invention.

FIGURE 2 is a sectional view taken along line 22 of FIGURE 1.

FIGURE 3 is a sectional view taken along line 33 of FIGURE 2.

FIGURE 4 is a view showing a portion of FIGURE 2 on an enlarged scale and also showing in greater detail the method of securing the brushes to the brush holders.

FIGURE 5 is a view illustrating a modified arrangement for connecting a brush holder with a spring steel support member.

FIGURE 6 is a sectional view of a brush holder shown in FIGURE 5.

FIGURE 7 is a plan view of the brush holder illus trated in FIGURE 6 and looking in the direction of the arrow designated by reference numeral 7.

FIGURE 8 is a perspective View of the spring steel support member and rivet that forms a part of the brush rigging illustrated in FIGURE 5 FIGURE 9 is a sectional view taken along line 99 of FIGURE 8.

FIGURE 10 is a sectional view taken along line Ill-10 of FIGURE 8.

Referring now to the drawings and more particularly to FIGURE 1, the reference numeral 10 generally designates an electric starting motor for driving a pinion 12 that is adapted to mesh with the ring gear of an engine to be cranked. The starting motor has a frame 14 which contains the armature and field coils and this frame supports the usual solenoid 16 which shifts the pinion through the linkages 18 and 20.

The frame 14 of the electric starting motor supports pole shoes 22, 24, 26, and 28 upon which are wound the field coils 30, 32, 34 and 36. The electric motor has the usual armature shaft 38 which supports the armature core and winding 40 and the commutator 42.

3,141,985 Patented July 21, 1964 "ice The brush rigging for the electric motor includes a pair of spring steel members 44 and 45 which are generally U-shapecl. It is seen that the spring steel member 44 supports a pair of brush holders 46 and 48 which are formed of a moldable plastic insulating material. The brush holder 46 is held to the spring steel member 44 by a rivet 50 which passes through an opening formed in the brush holder 46 and another opening formed in the spring steel member 44. In a similar fashion, the brush holder 48 is secured to an opposite side of the spring steel member 44 by a rivet 52 that passes through openings formed respectively in the brush holder and spring steel support 44.

It is seen from FIGURES 2 and 4 that the spring steel member 44 is secured to the frame 14 by a rivet 54 which has a square section 56. This square or rectangular section 56 fits within a complementary square or rectangular opening 58 formed in the spring steel member 44 and a complementary square opening 59 formed in housing 14. The rivet 54 also serves to hold a terminal 60 in place which is connected with the lead wire 62. The terminal 60 has a square opening receiving section 56. The opposite end of lead wire 62 is connected with a terminal 64 and it is seen that this terminal is held in place by a screw fastener 66 which is threaded into an opening 68 formed in the brush holder 48. The screw fastener 66 also passes through an opening in the brush 70 and thus serves to hold the brush and the terminal 64 in fixed relationship with the brush holder 48.

In a similar fashion, it is seen that the brush 72 is secured to brush holder 46 by a screw fastener 74. The screw fastener 74 also serves to hold a terminal 76 in place which is connected with the lead wire 78. The lead wire 7 8 is connected to one side of the field coil 32.

It will be appreciated that the brush 70 is grounded since it is connected to the frame 14 via the lead wire 62 and the terminal 60 which engages one side of the spring steel member 44. The spring steel member of course is at ground potential since it is in direct contact with the frame 14 and is secured thereto by the rivet 54.

The other spring steel member 45 is held to the frame 14 by a rivet 79 which has a section of square configuration that passes through square openings in the spring steel member 45, the frame 14 and a terminal 96. The spring steel member 45 supports brush holders 80 and 82 which are identical with the brush holders 46 and 48. The brush holder 80 supports a brush 84 whereas the brush holder 82 supports the brush 86. These brushes are held to the brush holders by screw fasteners 88 and 90 in a fashion identical with the securement of the brushes 70 and 72 to the brush holders 48 and 46. The fastener 88 holds a terminal 92 in place which is connected with lead wire 94. The lead wire 94 is connected with a terminal 96 and it therefore is seen that the brush 84 will be at ground potential since it is connected with the frame 14 via the lead wire 94.

The screw fastener 90 holds the terminal 98 in place and this terminal is connected with lead wire 100. The lead wire 100 is connected to the same side of the field coil 32 as is the lead wire 78.

It can be seen from the foregoing that the spring steel members 44 and 45 are supported directly by the frame 14 and are each electrically connected with the frame. It is also seen that the spring steel members 44 and 45 support the brush holders and that these spring steel members serve to urge the brushes into engagement with the commutator 42. It thus can be seen that the spring steel members serve to support the brushes but also serve to urge the brushes into engagement with the commutator 42. In the embodiment that has been illustrated, the brushes 84 and 70 are grounded whereas the brushes 72 and 86 are connected with the field coil 32.

Referring now more particularly to FIGURES through 10, a modified brush rigging is illustrated which may be substituted for the brush rigging that is shown inFIGURES 1 through4. The main difference between the brush rigging shown in FIGURES 5 through as compared to that shown in FIGURES 1 through 4 is the method of connecting the brush holders with the spring steel supports. In FIGURE 5, a commutator is once more designated by reference numeral 42 and a brush holder is designated by reference numeral 102. The brush holder 1.02 has a hole 104 that extends therethrough and has a tapered opening 106 as is better illustrated in FIGURES 6 and 7. The spring steel support member is designated by reference numeral 108 and it is seen that it is identical with the spring steel supports 44 and 45 with the exception that the member 10% is provided with tangs 110 and an arcuately extending struck out section 112. The spring support 108 has a square opening 113 the same as spring steel members 44 and 45 and a rivet 114 is illustrated which is the same as rivets 54 and 79.

In the arrangement of FIGURES 5 through 8, the ends of the spring steel member 108 are slipped into an opening 106 formed in the brush holder 102. After the ends are slipped into these openings, the tangs' 110 spring out and bite into the plastic material of the brush holder 102 to therefore tightly secure the brush holder 102 to the spring steel member 108.

It is seen from FIGURE 5 that a brush 115 is secured to the brush holder 102 by a screw fastener 116 which is threaded into the opening 104. The screw fastener 116 serves to hold a terminal 118 in place which is connected with a lead wire 120.

It will, of course, be appreciated that there will be two spring steel members 108 required for a given dynamoelectric machine and that these spring steel members will replace those illustrated in FIGURES 2 and 4. It can be seen that the primary difference between the arrangement illustrated in FIGURES 5 through 10 and that illustrated in FIGURES 2 through 4 resides in the construction of the plastic brush holder and its method of connection to the spring steel support members.

While the embodiments of the present invention as herein disclosed, constitute a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. In combination, a dynamoelectric machine having a frame, a generally U-shaped spring metal member, a

polygonal opening in said spring metal member, a complementary polygonal opening in said frame, a rivet having an outer configuration which is complementary to the openings in said spring metal member and frame passing through said openings and securing said spring metal member directly to said frame, said rivet also securing a first terminal in metal to metal contact with said spring metal member, brush holders formed of insulating material secured to opposite ends of said spring metal member, brushes carried by said brush holders and engageable with a rotatable current conducting means of said dynamoeleotric machine, at least one of said brushes being secured to one of said brush holders by fastening means that also secures a second terminal in place, and a conductor connecting said first and second terminals, said spring metal member forming a support means for said brush holders and also forming a biasing means for urging said brush holders toward said current conducting means.

2. In combination, a dynamoelectric machine having a metallic frame, a one-piece generally U-shaped spring metal member, a polygonal opening in said frame, a complementary polygonal opening in said spring metal memher, a rivet having an outer configuration which is complementary to the openings in said frame and spring metal member securing said spring metal member in direct metal to metal contact with said frame, first and second brush holders formed of insulating material secured to opposite ends of said spring metal member, brushes carried by said brush holders and engageable with a rotatable current conducting means of said dynamoelectric machine and conductor means connected with said brushes for transferring current between parts of said dynamoelectric machine and said brushes.

3. The dynamoelectric machine according to claim 2 wherein the brush holders have openings which receive the ends of said spring metal member and wherein said ends have tang means which bite into the material and the brush holders.

References Cited in the file of this patent UNITED STATES PATENTS 

1. IN COMBINATION, A DYNAMOELECTRIC MACHINE HAVING A FRAME, A GENERALLY U-SHAPED SPRING METAL MEMBER, A POLYGONAL OPENING IN SAID SPRING METAL MEMBER, A COMPLEMENTARY POLYGONAL OPENING IN SAID FRAME, A RIVET HAVING AN OUTER CONFIGURATION WHICH IS COMPLEMENTARY TO THE OPENINGS IN SAID SPRING METAL MEMBER AND FRAME PASSING THROUGH SAID OPENINGS AND SECURING SAID SPRING METAL MEMBER DIRECTLY TO SAID FRAME, SAID RIVET ALSO SECURING A FIRST TERMINAL IN METAL TO METAL CONTACT WITH SAID SPRING METAL MEMBER, BRUSH HOLDERS FORMED OF INSULATING MATERIAL SECURED TO OPPOSITE ENDS OF SAID SPRING METAL MEMBER, BRUSHES CARRIED BY SAID BRUSH HOLDERS AND ENGAGEABLE WITH A ROTATABLE CURRENT CONDUCTING MEANS OF SAID DYNAMOELECTRIC MACHINE, AT LEAST ONE OF SAID BRUSHES BEING SECURED TO ONE OF SAID BRUSH HOLDERS BY FASTENING MEANS THAT ALSO SECURES A SECOND TERMINAL IN PLACE, AND A CONDUCTOR CONNECTING SAID FIRST AND SECOND TERMINALS, SAID SPRING METAL MEMBER FORMING A SUPPORT MEANS FOR SAID BRUSH HOLDERS AND ALSO FORMING A BIASING MEANS FOR URGING SAID BRUSH HOLDERS TOWARD SAID CURRENT CONDUCTING MEANS. 